Lubricating oil compositions



United States Patent 3,326,801 LUBRlCA'llil IG OIL CUMPGSITIONS Roland T. Schlobohrn, Bethalto, and Herbert I). Millay, East Alton, IiL, assignors to Shell Oil Company, New York, N.Y., a corporation of Delaware No Drawing. Filed July 16, 1965, Ser. No. 472,701 8 Uaims. (Cl. 252--51.5)

This invention relates to novel lubricating oil compositions. More particularly, the invention is concerned with new, novel and superior lubricating oil compositions for use in internal combustion engines.

The use of ashless polymeric compounds as detergents in lubricating oil compositions is well known in the art. Polymers of this type are generally high molecular weight nitrogen-containing polymers such as copolymers of vinyl pyridine or vinyl pyrrolidone and long-chain alkyl methacrylates, or mono(polyolefin)succinimides derived from mono (polyolefin)succinic anhydride and polyalkylene polyamines. Although polymers and copolymers of this type are excellent detergent-dispersant oil additives they lack corrosion and wear inhibiting properties and therefore require the presence of fortifying agents capable of inhibiting corrosion and wear. The use of fortifiers in conjunction with such detergents, however, presents new problems such as interaction of the additives mixture or interference with each others functions resulting in general inetfectivenes of such compounded lubricants, particularly when they are used in engines operating under stop-and-go conditions or severe temperature and pressure conditions. Where some such additive combinations in lubricants have been found to be successful, cost increase, short lubricant life and their restrictive use to special types of engines has made use of such lubricants unattractive.

It has now been discovered that an excellent multifunction lubricating oil composition can be made useful in various types of engines such as 4-stroke and 2-stroke engines and particularly for use in the latter type engines by incorporationg in a lubricating oil base a small amount of from 0.1% to about 20%, preferably from 2-8% of an oil-soluble reaction product of (1) a polyamide of a polyalkylene polyamine and an iso-fatty acid or mixture of an iso-fatty acid and a straightchain fatty acid having from 8 to 22 carbon atoms and having at least one and preferably a plurality of from 1-100 (2-50) free basic amino nitrogen atoms in the molecule or derivatives thereof with (2) mixture of condensation product of an alkyl hydroxyaromatic compound and low molecular weight aldehyde.

The polyamides (1) of polyalkylene polyamine and isofatty acids or mixtures of straight-chain fatty acids and iso-fatty acids each having from 8 to 22 carbon atoms are prepared by reacting about the mole of a polyalkylene polyamine with 1-4 moles of an iso-fatty acid or mixtures thereof as noted above at between 100 and 250 C., preferably at 150-200" C. for about -24 hours in an enclosed vessel and under atmospheric conditions until the polyamide, preferably a diamide is formed and the product cooled and recovered, The polyamide thus formed can be condensed with from 1-20 moles each of an aldehyde and an alkylated hydroxyaromatic compound, e.g.,

alkyl phenol in a Mannich synthesis. In general, from 1-4 moles each of the aldehyde and an alkyl phenol is used for every mole of polyamide compound (1) and the reaction can be carried out at 35250 C., in the presence or absence of a solvent. A preferred method is to interact the polyamide containing free basic amino nitrogen in the molecule with from 1-4 moles each of an aliphatic aldehyde and a C alkyl phenol at 25-200 C.

23,32,801 Patented June 20, 1967 The iso-fatty acids used to form the polyamides with polyalkylene polyamines included saturated and unsaturated fatty acids having from 8 to 22 carbonatoms such as iso-oleic acid, dimerized or trimerized unsaturated fatty acids having from 16 to 20 carbon atoms such as dimerized oleic and linoleic acids, or mixtures of said unsaturated acids and/or hydrogenated derivatives thereof such as iso-stearic acid or mixtures of iso-fatty acids and straight-chain C1240 saturated fatty acids such as lauric, myristic, palmitic and/0r stearic acids. When mixtures are used, the straightchain fatty acids comprise 5-30 mole percent and the balance (70-95 mole percent) being the iso-fatty acids or branch-chain fatty acids. The polyamines used to form the diamides include diethylene triamine, triethylene tetr-amine, tetraethylene pentamine, tripropylene tetramine, tetrapropylene pentamine and the like Other suitable polyamines are the result of polymerizing ethylene imine to a molecular weight of from 500 to 40,000. Specific conditions for making the diamides are by reacting approximately one mole of a polyamine, e.g., tetraethylene pentamine, and one or more moles of saturated and/or unsaturated fatty acids, e.g., iso-oleic acid or dimerized oleic acid or iso-stearic acid or mixtures of stearic and is-stearic acids at between C. and 250 C. for a period of 1-10 or more hours, preferably under atmospheric pressure. For example, 1 mole of alkyl substituted diethylene triamine H NCH CH N(C H )CH CH NH and two moles of iso-oleic acid were mixed and heated at -200 C. for about 1-10 hours in an enclosed vessel under atmospheric conditions until the diamide was formed, after which the reaction was cooled and the end product has the following formula:

(Ia) RCONHCH CHN (C H CH CH NHCOR where R is oleyl radical. Other diamides include (Id) dioleylamide of diethylene triamine, (Ic) dimerized oleylamide of diethylene triamine, (Id) dimerized linoleylamide of diethylene triamine, (12) mixed diand trimerized oleylamide of diethylene triamine, (If) diisooleyamide of diethylene triamine, (Ig) diisooleylamide of N-2-aminoethyl piperazine, (Ih) diamide of tetraethylene pentamine and iso-stearic acid, (Ii) diamide (if tetraethylene pentamine and a mixture of 10 mole percent stearic acid and 90 mole percent iso-stearic acid, and mixtures thereof.

The aldehydes useful in forming reaction products of this invention include aliphatic aldehydes, e.g., formaldehyde (paraformaldehyde) acetaldehyde, butyraldehyde or aromatic aldehydes, e.g., benzaldehyde or salicylaldehyde or heterocyclic aldehydes, e.g., furfural and mixtures thereof.

The alkylated hydroaromatic compounds include C alkyl monoand polyhydroxy aromatics such as C alkyl phenol, naphthol, anthranol and preferably C alkyl phenol such as nonyl phenol, dodecyl phenol, dinonyl phenol, benzyl phenol and mixtures thereof.

The following examples illustrate the present invention.

Example I.One mole of diamide identified above as (Ij) was reacted with 2 moles each of formaldehyde and dodecyl phenyl at around 50160 C. for about 5 hours. The final product was oil-soluble and possessed excellent detergent and sludge inhibiting properties.

Example II.Diisostearamide of tetraethylene pentamine was reacted with 2.5 moles each of formaldehyde and dodecylphenol under reaction conditions of Example I and the final reaction product was oil-soluble and exhibited excellent detergent and corrosion inhibiting properties.

The following examples prepared under similar conditions as described for Examples I and II are also illustrative examples of the present invention:

Example ILL-Reaction product of 1 mole diarnide (Ia)-2 moles formaldehyde-2 moles decylphenol.

Example IV.-Reaction product of 1 mole of diamide (Ic)-1 mole formaldehyde-1 mole dodecylphenol.

Example V.Reaction product of 1 mole of diarnide (ID-3 mole-s formaldehyde-3 moles dodecylphenol.

Example VL-Reaction product of 1 mole of diamide (Ij)-3 moles formaldehyde-3 moles C1448 alkylphenol.

Example VH.-Reaction product of 1 mole of (Ilt)-2 moles of formaldehyde-2 moles dodecylphenol.

Example VlIL-Reaction product of 1 mole of (111)-2 moles of formaldehyde-2 moles benzylphenol.

Example IX.Reaction product of 1 mole of (Ih)-2 moles of acetaldehyde-Z moles C1448 alkylphenol.

Example X;.Reaction product of 1 mole of diamide (Ic)-1 mole of formaldehyde-1 mole C alkyl naphthanol.

Reaction products of the present invention can be added in small amounts of from 0.1% to about preferably from 1% to 15% in various lubricants of the natural and/or synthetic type such as mineral lubricating oils in the viscosity range of from SAE 5W to SAE 140, preferably in the SAE viscosity range of 2090. The mineral lubricating oils can be of the same base stock or blends of different base stocks or blends of mineral lubricating oil and synthetic lubricants such as polymerized olefins, organic esters of organic and inorganic acids, e.g., di-2-ethylhexyl sebacate, pentaerythritol esters of mixed C fatty acids; polyalkyl silicone polymers, e.g., dimethyl silicone polymer, and the like. If desired, the synthetic lubricants may be used as the sole base lubricant.

Mineral lubricating oils which are particularly desirable for use in compositions of this invention were obtained from West Texas Ellenburger crudes, East Texas crudes, Oklahoma crudes, California crudes. A useful refined oil therefrom has the following properties:

Gravity, API, min. 26.5 Pour point, F., max. 10 Flash, COC, F., min. 390 Viscosity, SUS at 100 F. 120160 Viscosity index, min. 95

Another such oil is a SAE 30 mineral oil having the following properties:

Gravity, API, rnin. 26.5

Although reaction products of the present invention are useful additives in motor oils, diesel oils, various industrial oils such as hydraulic fluids, gear oils, cutting fluids and the like, they are particularly useful in lubricants for 2-stroke engines. Two-stroke engine lubricants containing the reaction product of the present invention can be used in 2-stroke engines operating on neat or leaded gasolines. When leaded gasolines are used the presence of a halogen scavenger is normally desirable although not necessary. Thus, when leaded gasoline is used the lead compounds can be tetramethyl, tetraethyl, ethylmethyl, diethyl dimethyl, triethyl methyl lead and mixtures thereof. The scavengers include saturated and unsaturated halogenated (Cl, Br, I) olefins such as ethylene dibromide, ethylene dichloride or mixtures thereof. Still other scavengers include organic halide wherein the halogen atom is attached directly to an unsaturated carbon atom there are mentioned haloethylenes, e.g., iodoethylene, 1,1-dichloroethylene, 1,2-dichloroethylene, 1,2- dibromoethylene, trichloroethylene, tetrachloroethylene;

halogen derivatives of butadiene, e.g., 1-chloro-l,3-butadiene, 2 chloro 1,3 butadiene, 1,1,2,3,4,4-hexachlorobutadiene, aryl halides, e.g., chlorobenzene, bromobenzene, dichloro'benzene, dibromobenzene, diiodobenzene, trichlorohenzene, tribromobenzene, tetrachlorobenzene, tetrailuorobenzene, hexafluorobenzene, halogen derivatives of unsaturated heterocyclic compounds, e.g., 2-chloropyridine, 3-chloropyridine, 4-chloropyridine, 3-bromopyridine, 3-chloropyrrole, 2-chlorothiophene and certain substituted haloacetylenes, e.g., l-chlorohexyne-l, although halogen derivatives of the acetylenes are in general unlikely to be suitable. Preferred halides are those which contain the greatest amount of halogen per unit weight of halide consistent with adequate oil solubility. The fuel can also contain organic phosphites, phosphates, e.g., tricresyl phosphate, diphenyl cresyl phosphate, or boron esters and the like.

An excellent lubricant base for use in Z-stroke engines containing the reaction product of the present invention is an oil blend consisting of a mixture of from 10% to 50% bright stock and from to 50% of a high viscosity index (80-140 VI) mineral lubricating oil having a viscosity at F. SUS of from 100 to 600. A portion of the high viscosity oil can be replaced with a medium viscosity oil.

An oil base mixture for 2-stroke engines consists of (a) a bright stock fraction rich in aromatics (570%) and Which has a viscosity index of at least 80, preferably between 90 and and is obtained during the refining of mineral oils from the short residue after the distillate fractions have been removed. The short residue is dewaxed and deasphalted and if desired, solvent and claytreated. The rafdnate which remains after this treatment is called bright stock. Table I and II illustrate examples of useful bright stocks.

TABLE I.EXAMPLES OF TYPICAL BRIGHT STOCKS TABLE II.SPECIFICATIONS FOR TYPICAL MID-CONTINENT BRIGHT STOCKS Unfiltered Filtered Gravity API minimum 25. 5 24. 5 25. Color, N PA 8+ Dark 6.?

Green Pour Point, F., maximum 10 10 10 Flash, F., minimum 540 580 545 F re, F., minimum 6, 5 655 610 Viscosity, SUS, 210 F 170 200-215 150-160 90 90 90 The other portion of the oil blend is a high viscosity index lubricating oil distillate fraction and specifically is a refined distillate fraction having a viscosity index of at least 80, preferably 90410, an SUS viscosity at 100 F. in the range of 100-600, and containing substantial proportions of heterocyclic aromatics such as sulfur-containing aromatics (210%) such as benzothiophenes, dibenzothiophenes, thiophenacenaphthylenes, thiophenophenanthrenes, thiophenopyrines, etc. Such a typical petroleum fraction will be referred to as fraction (Y) and such a fraction derived from an East Texas crude has the following proper-ties:

Viscosity, SUS, at 100 F. 25-0 Viscosity index 90-95 Analysis (incremental ultraviolet absorption):

Monoaromatics percent 14 Polyaromatics of which 13-17% are diaromatics containing thiophenic structures, e.g., hemeand dibenzothiophenes do 21 Polar-containing resins do 3 Essentially balance-saturates.

Base blends which are particularly preferred are:

Any of the oil bases may also contain fortifying agents such as viscosity index improvers (e.g., polymeric acrylic esters), pour point depressants (e.g., methacrylate polymers), oxidation inhibitors, e.g., bis(2,6-di-t-butyl-4-hydroxy phenyl)methane, metal deactivators, e.g., di-salicylal ethylene diimine, rust inhibitors, e.g., the condensation product of maleic anhydride and long-chain alkenes, anti-foaming agents e.g., silicone polymers, EP additives, provided that such EP additives do not contain halogens, e.g., triphenyl phosphate, and anti-seizure agents, e.g., acidless tallow or a non-drying fatty oil, e.g., castor oil. The term gasoline as used in 2-stroke engines is intended to mean a hydrocarbon oil, or a mixture of a hydrocarbon oil with an alcohol, distilling substantially continuously at atmospheric pressure throughout the temperature range 10 C. to 250 C. and containing a lead tetra-alkyl, for example, tetraethyl lead, tetramethyl lead, ethyl triethyl lead, diethyl dirnethyl lead, triethyl methyl lead or mixtures thereof. The hydrocarbon oil Will normally be derived from petroleum but may be derived from other sources, e.g., from coal or from synthetic processes. The gasoline may contain other anti-knock agents, for example, methyl cyclopentadienyl manganese tricarbonyl, and any of the additives of fortifying agents known to the art, e.g., vapor pressure modifiers such as butanes, co-anti-knock agents, e.g., tertiary butyl acetate, scavengers, e.g., alkyl halides, deposit modifiers, e.g., tritolyl phosphate, anti-icing additives, e.g., isopr-opyl alcohol, anti-foaming agents, e.g., silicones, anti-oxidants, e.g., 2,4-methyl-6tertiary butyl phenol or di sec. butyl para phenylene diamine and dyestuffs or coloring agents.

The reaction product of the present invention can be used in amounts of from 0.1% to 10% in conventional motor lubricants such as used in 4-stroke engines, or in gear lubricants and the like. When this reaction product is used as a lubricant for 2-stroke engines the additive is used in higher concentrations of from 1% to 25%, preferably from 3% to 10%. The compounded lubricant is blended with a suitable fuel, e.g., gasoline, diesel fuel, etc., in amounts of from about 0.2 to about 10 pints, preferably 1-5 pin-ts of lubricant per gallon of fuel, e.g., neat or leaded gasoline or the lubricant of the present invention can be used in the ratio of 1 part of oil compositions to -100 parts of fuel. Generally, 1 part of the oil composition to to 50 parts of fuel is preferred.

The following examples illustrate lubricating oil compositions of the present invention:

Composition It Example I reaction product percent wt 5 SAE 30 mineral lubricating oil Balance Composition II:

Example II reaction product percent wt 7 SAE 40 mineral lubricating oil Balance Composition III:

Example V reaction product percent wt 5 1,1 bis(3,5 ditert butyl 4 hydroxyphenyl)methane do 0.5

SAE 30 mineral lubricating oil Balance Composition IV:

Example VI reaction product percent wt 5 1,1 bis(3,5 ditert butyl 4 hydroxyphenyl)methane percent 0.5

Tricresyl phosphate do 0.8

10W-30 mineral lubricating oil Balance Composition V:

Example VII reaction product -percent wt 5 Base blend (A) Balance Composition VI:

Example V reaction product percent wt 5 Base blend (A) Balance Composition VII:

Example VI reaction product -percent wt 10 Base blend (A) Balance The lubricating oil compositions were tested as 2- stroke engine lubricants in Homelight motor-generators, and in Mercury 650 and Johnson 40 HP Outboard 2- stroke engines under conditions shown below.

Homelite engine test conditions Test conditions and duration: Full power for 15 hours.

Test fuel: Shell gasoline leaded to 3 ml./gal. motor mix TEL and containing 0.2 theory phosphorus as diphenyl cresyl phosphate Fuel/oil ratio: 15/1 Base oil: Blend A Mercury 650 outboard engine test conditions Test conditions and duration: hours alternate periods of 5 minutes idle and 55 minutes full-throttle at 5000 r.p.m.

Test fuel: Shell gasoline leaded to 3 ml./gal. motor mix TEL and containing 0.2 theory phosphorus as diphenyl cresyl phosphate Fuel/ oil ratio: 20/ 1 Base oil: Blend C Johnson 40 HP outboard engine test conditions Test conditions and duration: 98-hour test alternate 5 minutes idle, 55 minutes full throttle, 4800 r.p.m. with one hour shutdown after each 7 running hours Test fuel: Shell gasoline leaded to 3 ml./ gal. motor mix TEL and containing 0.2 theory phosphorus as diphenyl cresyl phosphate Fuel/oil ratio: 50/1 Base oil: Blend C Compositions V, VI and VII tested in the above three engines under conditions described gave excellent results, With essentially no ring sticking (2829 rating where 30 is perfect); no piston skirt lacquer deposits (7-10 where 10 is perfect); no exhaust port blockage (9.4-10 Where 10 is perfect); combustion chamber deposit (7.58.2 where 10 is perfect) and piston scuffing (8.5-9.5 Where 10 is perfect). Compositions X and Y containing 5% each of additive (Ih) and (Ij) when tested in the Homelite engine under similar test conditions described above resulted in reduction of engine cleanliness rating of from 3% to 15% when compared to results obtained with Compositions V, VI and VII as noted above.

Examples V, VI and VII reaction products and intermediate compounds (Ih) and (1 were subjected to differential thermal analysis and it was found that the reaction products of Examples V, VI and VII begin thermal decomposition in the presence of air, about 100 F. higher than the compounds (Ih) and (Ij) indicating that the decomposition rate of (Ih) and (Ij) is much greater than that of Examples V, VI and VII reaction products of the present invention. This is clear evidence that the reaction products of the present invention are much more stable than the intermediate compounds (Ih) and (Ij).

Compositions of the present invention can be used also as gear lubricants, as truck, railroad and automotive lubricants, as hydraulic fluids, greases, fuels and the like.

We claim as our invention:

1. A lubrication oil composition comprising a major amount of lubricating oil and containing a minor amount, sufficient to impart detergency, of an oil-soluble reaction product prepared by reacting at 25-250 C. a polyamide of an iso-fatty acid and a polyalkylene polyamine with from 1-4 moles each per mole of the polyamide of an aldehyde selected from the group consisting of formaldehyde, paratormaldehyde, acetaldehyde, butyraldehyde, benzaldehyde, salicylaldehyde, furfural and mixtures thereof and a C alkyl phenol.

2. A lubricating oil composition comprising a major amount of lubricating oil and from 0.1% to 20% of an oil-soluble reaction product prepared by reacting at 25- 250 C. a polyamide of an iso-fatty acid having from 8 to 22 carbon atoms and a polyalkylene polyamine with from 1-4 moles each per mole of the polyamide of an aldehyde selected from the group consisting of formaldehyde, paraformaldehyde, acetaldehyde, butyraldehyde, benzaldehyde, salicylaldehyde, furfural and mixtures thereof and a C alkyl phenol.

3. A lubricating oil composition comprising a major amount of mineral lubricating oil and from 0.1% to 20% of an oil-soluble reaction product prepared by reacting at 25-250 C. the diamide of iso-stearic acid and tetraethylene pentamine with from 1-4 moles each per mole of the diamide of formaldehyde and C alkyl phenol.

4. A lubricating oil composition comprising a major amount of mineral lubricating oil and from 0.1% to 20% of an oil-soluble reaction product prepared by reacting at 25-250 C. the diamide of tetraethylene pentamine and a mixture of iso-stearic and stearic acid with from 1-4 moles each per mole of the diamide of formaldehyde and dodecyl phenol.

5. A lubricant for 2-stroke engines employing a lubricant-fuel mixture, said lubricant consisting of a blend of -50% bright stock and 90-50% mineral lubricating oil having a viscosity index of 80-140 and a SUS at 100 F. of

100-600 and having incorporated therein from 3-10% of an oil-soluble reaction product prepared by reacting at 25-250 C. a polyamide of an iso-fatty acid and a polyalkylene polyamine with from l-4 moles each per mole of the polyamide of an aldehyde selected from the group consisting of formaldehyde, paraformaldehyde, acetaldehyde, butyraldehyde, benzaldehyde, salicylaldehyde, furfural and mixtures thereof and a C alkyl phenol.

6. A lubricant for 2-stroke engines employing a lubricant-fuel mixture, said lubricant consisting of a blend of 10-50% bright stock and 90-50% mineral lubricating oil having a viscosity index of -140 and a SUS at 100 F. of 100-600 and having incorporated therein from 33-10% of an oil-soluble reaction product prepared by reacting at 25-250 C. a polyamide of an iso-fatty acid having from 8 to 22 carbon atoms and a polyalkylene polyamine with from 1-4 moles each per mole of polyamide of an aldehyde selected from the group consisting of formaldehyde, paraform aldehyde, acetaldehyde, 'butyraldehyde, benzaldehyde, salicylaldehyde, furfural and mixtures thereof and a C alkyl phenol.

7. A lubricant for 2-stroke engines employing a lubricant-fuel mixture, said lubricant consisting of a blend of 10-50% bright stock and -50% mineral lubricating oil having a viscosity index of 80-140 and a SUS at F. of 100-600 and having incorporated therein from 3-10% of an oil-soluble reaction product prepared by reacting at 25-250 C. the diamide of iso-stearic acid and tetraethylene pentamine with from 1-4 moles each per mole of diamide of formaldehyde and C alkyl phenol.

8. A lubricant for Z-stroke engines employing a lubricant-fuel mixture, said lubricant consisting of a blend of 10-50% bright stock and 90-50% mineral lubricating oil having a viscosity index of 80-140 and a SUS at 100 F. of 100-600 and having incorporated therein from 3-10% of an oil-soluble reaction product prepared by reacting at 25 -250 C. the diamide of tetraethylene pentamine and a mixture of iso-stearic and stearic acid with from 1-4 moles each per mole of the diamide of formaldehyde and dodecyl phenol.

References Cited UNITED STATES PATENTS 2/1965 Benoit 25251.5 X 2/1966 Piatt et al. 44-58 X 

1. A LUBRICATION OIL COMPOSITION COMPRISING A MAJOR AMOUNT OF LUBRICATING OIL AND CONTAINING A MINOR AMOUNT, SUFFICIENT TO IMPART DETERGENCY, OF AN OIL-SOLUBLE REACTION PRODUCT PREPARED BY REACTING AT 25*-250*C. A POLYAMIDE OF AN ISO-FATTY ACID AND A POLYALKYLENE POLYAMINE WITH FROM 1-4 MOLES EACH PER MOLE OF THE POLYAMIDE OF AN ALDEHYDE SELECTED FROM THE GROUP CONSISTING OF FORMALDEHYDE, PARAFORMALDEHYDE, ACETALDEHYDE, BUTYRALDEHYDE, BENZALDEHYDE, SALICYLALDEHYDE, FURFURAL AND MIXTURES THEREOF AND A C1-20 ALKYL PHENOL. 